• 제목/요약/키워드: Milling yield

검색결과 102건 처리시간 0.022초

단일벽 탄소 나노튜브의 길이와 지름에 따른 분류 (Separation of Single-Walled Carbon Nanotubes by Length and Diameter)

  • 오영석;이덕진;장윤석;최재붕;김영진;백승현
    • 한국정밀공학회지
    • /
    • 제23권3호
    • /
    • pp.171-178
    • /
    • 2006
  • The sonication mettled is widely used with surfactants to suspend individual single-walled carbon nanotubes in solution, and it is well known that sonication-induced tube cutting occurs. Recently, it is found out that ultrasonicated nanotubes yield simultaneous separation by tube length and diameter. Nanotubes that have been cut shortest possess the greatest enrichments of large-diameter species. In this study, single-walled carbon nanotubes are cut using a ball milling method. Similar fracture behavior is observed fur the ball milled nanotubes: i.e., large diameter tubes are cut shorter. The ability to separate carbon nanotubes by diameter and length will contribute to tile development of nanotube-based applications.

밀의 경도가 밀가루 제품에 미치는 영향 (Effects of Flour Products on Wheat Hardness)

  • 김혁일;하영득
    • 한국식품영양과학회지
    • /
    • 제20권6호
    • /
    • pp.653-662
    • /
    • 1991
  • aThe terms of hard and soft as applied to wheats are descriptions of the texture of the kernel. A hard wheat kernel required greater force to cause it to disintegrate than those a soft wheat kernel. Factors than can affect the measurement of hardness outnumber those that affect hardness itself. Kernel texture is the most important single characteristic that affects the functionality of a common wheat. It affect the way in which must be tempered for milling ; the yield and the particle size, and density of flour particles ; and the end use properties in milling, breadmaking, production of soft wheat products, and noodle-making. Papers are reviewed from various sources not only hardness but flour functionality.

  • PDF

승용차용 CYLINDER ROD 소재의 밀링 적삭 특성 연구 (A Study on the Machining Charcterisitics of Milling of cylinderical Rod Materials for Passenger Car)

  • 채왕석
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 1996년도 춘계학술대회 논문집
    • /
    • pp.143-148
    • /
    • 1996
  • In this paper, we have studied internal quality including chemical compositions, microscopic structure and nonmetalic inclusion of test materials. We have analyzed dynamic characteristics of cutting force of milling including tensile strength value hardness etcs. Test materials are used the tempered carbon steel and the non-tempered carbon steel. The obtained results are as follows: 1.In analyzing internal quality, the tempered carbon steel have typical martensite structure and the non-tempered carbon steel have ferrite+pearlite structure. 2.Yield strength, tensile strength and hardness value are in the non-tempered carbon steel but elongation is maximum value in the tempered carbon steel. 3.Cutting force is smaller non-tempered carbon steel than tempered carbon steel when feed speed and depth of cut is constant. 4.Cutting force is smaller to the tempered carbon steel and smaller non-tempered carbon steel than tempered carbon steel when cutting conditions

  • PDF

Effects of Microbe-inoculated Expanded Rice Hull on Growth, Yield and Grain Quality of Rice

  • Kim, Young Jun;Nunez, John Paolo;Seo, Pil Dae;Ultra, Venecio U. Jr.;Lee, Sang Chul
    • 한국작물학회지
    • /
    • 제58권1호
    • /
    • pp.78-83
    • /
    • 2013
  • The excessive and indiscriminate use of chemical fertilizers in the past has brought serious soil and other environmental problems so alternatives over this agrochemical are being searched. Our study focuses on the effects of expanded rice hull inoculated with selected beneficial microorganisms on growth (through agronomic characters), yield and yield components, and grain quality indices of rice. Results showed that favorable effects of different expanded rice hull preparations were not readily apparent at vegetative stage and only treatments with supplemental chemical fertilizer application were comparable with the conventional practice. Expanded rice hull combined with 50% rate of chemical fertilizer exhibited a significantly higher yield (6,471 kg $ha^{-1}$) over conventional practice (5,719 kg $ha^{-1}$). Good milling quality indices were observed in treatments having 50% chemical fertilizers plus alternatives from expanded rice hull. Finally, we demonstrated that chemical fertilizer rate can potentially be reduced into 50% if combined with expanded rice hull, and show even better output than chemical fertilizer alone.

농축산바이오매스의 고온 혐기성 생분해도 평가 (Thermophilic Anaerobic Biodegradability of Agro-industrial Biomasses)

  • 허남효;강호;정지현;이승헌
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
    • /
    • pp.514-517
    • /
    • 2009
  • Anaerobic biodegradability(AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical Methane Potential(BMP) test has been carried out to evaluate the methane yield of agro-industrial biomasses such as cattle manure, Italian ryegrass(IRG), Oats, Rye and Barley as the forage crops, Rush, the sludges produced from milling and slaughterhouse wastewater treatment plant(SMWTP, SSWTP). In the condition of thermophilic anaerobic digestion, the ultimate methane yield and anaerobic biodegradability of forage crops ranged from 0.367 to $0.452LCH_4$/gVS of methane yield with AB having the range of about 77.0 to 87.3%. On the other hand, that of other substrate showed low figures compared with the forage crops because of low VS content and C/N ratio. Therefore, the forage crops could be used as a good substrate to produce much more the methane in anaerobic digestion.

  • PDF

실리콘 wafer sludge로부터 얻어진 SiC의 단광화 기술 (Briquetting of Waste Silicon Carbide Obtained from Silicon Wafer Sludges)

  • 구성모;윤수종;김혜성
    • 한국분말재료학회지
    • /
    • 제23권1호
    • /
    • pp.43-48
    • /
    • 2016
  • Waste SiC powders obtained from silicon wafer sludge have very low density and a narrow particle size distribution of $10-20{\mu}m$. A scarce yield of C and Si is expected when SiC powders are incorporated into the Fe melt without briquetting. Here, the briquetting variables of the SiC powders are studied as a function of the sintering temperature, pressure, and type and contents of the binders to improve the yield. It is experimentally confirmed that Si and C from the sintered briquette can be incorporated effectively into the Fe melt when the waste SiC powders milled for 30 min with 20 wt.% Fe binder are sintered at $1100^{\circ}C$ upon compaction using a pressure of 250 MPa. XRF-WDS analysis shows that an yield of about 90% is obtained when the SiC briquette is kept in the Fe melt at $1650^{\circ}C$ for more than 1 h.

탄소 나노튜브의 길이와 지름에 따른 분류 및 절단 메커니즘에 대한 연구 (Length and Diameter Separation of Single Walled Carbon Nanotubes)

  • 백승현;오영석;홍승현;이덕진;장윤석;김영진;최재붕
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2005년도 춘계학술대회 논문집
    • /
    • pp.1159-1163
    • /
    • 2005
  • The Sonication method is widely used with surfactants to suspend individual single walled nanotubes in solution, and it is well known that sonication-induced tube cutting occurs. Recently, it is found out that ultrasonicated nanotubes yield simultaneous separation by tube length and diameter. Nanotubes that have been cut shortest possess the greatest enrichments of large-diameter species. In this study, we cut single walled carbon nanotubes using a ball milling method and find out similar behavior compared to the sonication process Cutting mechanisms are also investigated using continuum approaches.

  • PDF

산화물 분산강화형 316L 스테인리스강의 제조와 특성 연구 (Fabrication and Characterization of ODS 316L Stainless Steels)

  • 김민호;류호진;김성수;한창희;장진성;권오종
    • 한국분말재료학회지
    • /
    • 제16권2호
    • /
    • pp.122-130
    • /
    • 2009
  • Austenitic oxide-dispersion-strengthened (ODS) stainless steel was fabricated using a wet mixing process without a mechanical milling in order to reduce contaminations of impurities during their fabrication process. Solution of yttrium nitrate was dried after a wet mixing with 316L stainless steel powder. Carbon and oxygen contents were effectively reduced by this wet processing. Microstructural analysis showed that coarse yttrium silicates of about 150 nm were formed in austenitic ODS steels with a silicon content of about 0.8 wt%. Wet-processed austenitic ODS steel without silicon showed higher yield strength by the presence of finer oxide of about 20 nm.

금속 브롬화물의 첨가에 따른 금속 할라이드 페로브스카이트 나노결정의 광학적 특성 변화 (Optical Properties of Metal Halide Perovskite Nanocrystals with Addition of Metal Bromide)

  • 윤석진;최지훈
    • 한국표면공학회지
    • /
    • 제52권6호
    • /
    • pp.334-341
    • /
    • 2019
  • Organometal halide perovskite materials have attracted much attention in the photovoltaic and light emitting devices due to the compositional flexibility with AMX3 formula (A is an organic amine cation; M is a metal ion; X is a halogen atom). The addition of homovalent or heterovalent metal cations to the bulk organohalide perovskites has been performed to modify their energy band structure and the relevant optoelectronic properties by ligand-assisted ball milling. Here, we report CH3NH3Pb1-xMxBr3 nanocrystals substituted by metallic cations (M is Sn2+, In3+, Bi3+; x = 0, 0.01, 0.02, 0.05, 0.1, 0.2). Photoluminescence and quantum yield was significantly reduced with increasing metallic cations content. These quenching effect could be resulted from the metal cations that behave as a non-radiative recombination center.

Hydroxyapatite가 도핑된 Ti-6Al-4V 구형 분말의 전기방전 소결 및 소결체 특성에 관한 연구 (A Study of Electro-Discharge-Sintering of Ti-6Al-4V Spherical Powders Doped with Hydroxyapatite by Spex Milling and Its Consolidation Characteristics)

  • 조유정;김영훈;조예현;김민재;김현수;김승우;박정환;이원희
    • 한국분말재료학회지
    • /
    • 제20권5호
    • /
    • pp.376-381
    • /
    • 2013
  • Spherical Ti-6Al-4V powders in the size range of 250 and 300 ${\mu}m$ were uniformly doped with nano-sized hydroxyapatite (HAp) powders by Spex milling process. A single pulse of 0.75-2.0 kJ/0.7 g of the Ti-6Al-4V powders doped with HAp from 300 mF capacitor was applied to produce fully porous and porous-surfaced Ti-6Al-4V implant compact by electro-discharge-sintering (EDS). The solid core was automatically formed in the center of the compact after discharge and porous layer consisted of particles connected in three dimensions by necks. The solid core increased with an increase in input energy. The compressive yield strength was in a range of 41 to 215 MPa and significantly depended on input energy. X-ray photoelectron spectroscopy and energy dispersive x-ray spectrometer were used to investigate the surface characteristics of the Ti-6Al-4V compact. Ti and O were the main constituents, with smaller amount of Ca and P. It was thus concluded that the porous-surfaced Ti-6Al-4V implant compacts doped with HAp can be efficiently produced by manipulating the milling and electro-discharge-sintering processes.